The main objectives of this research are: 1) to identify deficits in social-communicative skills and social concepts specific to autism and 2) to examine the relationship between social-communicative skills, social concepts, and language abilities in autistic children. Social-communicative skills demonstrated in two interaction sessions, one with a trained experimenter and one with the mother, will be compared for autistic, mentally retarded, and normal children matched on mental age. Social concepts, consisting of person permanence, the capacity for self-recognition, and the ability to discriminate facial expressions will also be compared across groups. The nonverbal social-communicative skills and social concepts of autistic children who show some language comprehension and production will be compared with tne nonverbal communicative skills and social concepts of autistic children who show no receptive or expressive language abilities. This comparison will determine which particular social skills and concepts are most highly associated with language acquisition within the autistic group. Furthermore, we will assess whether the social measures contribute to an estimation of level of language ability in addition to the association already established between representational play skills and language. In this way, we will identify a set of social and cognitive variables that relate independently to the level of language capacities. The language abilities of the low-language autistic children will be retested after 8 months in order to assess whether those variables concurrently related to language capacities also predict any gains in language abilities over time. The identification of particular social-communicative skills and concepts which are deficient in autistic children and relate to their language capacities is critical for intervention. In our previous research, we delineated specific cognitive factors related to language acquisition. The specification of social-communicative precursors of language acquisition is the second, and final step, in designing an intervention project aimed at enhancing the development of language abilities in verbally deficient autistic children. Basic language skills are crucial if autistic individuals are to develop some degree of competence and independence.